Olefin-terminated PIB

AUyl telecheUc PIBs have been obtained by end quenching with aUyltrimethylsi-lane (ATMS) [19, 124], methallyltrimethylsilane [19], tetraaUyltin, or aUyltributyltin (R. Faust, B. Ivan unpublished results). In the functionahTation reactions jS-proton abstraction should generally be avoided. Quantitative jS-proton abstraction with hindered bases reported recently, however, is a valuable method to produce ejto-olefin terminated PIB in one pot [125]. 

Synthesis of PIB prepolymers. fm-Chlorine-telechelic PIB (Mn=4,000 MVf/Mn 1.09) (7), and an allyl-telechelic PIB (Mn=9,500 Mw/Mn 1.14) (7,8) were prepared by living carbocationic polymerizations. The tert-chlorine ended PIB was quantitatively dehydrochlorinated (9) to -C(CH3)=CH2 terminated polymer. Both olefin-telechelic PIBs were then hydroborated and oxidized (10) to prepare the primary hydroxyl termini. The hydroxyl-telechelic polymers were esterified with methacryloyl chloride to methacrylate-telechelic PIBs, MA-PIB-MA (11). 

Poly (olefin-ester) multiblock copolymers belong to a quite new and fast developing class of polyester elastomers [58-60]. The copolymer with PBT rigid segments and flexible polyisobutylene (PIB) segments was prepared by polycondensation in the molten state with DMT, BD, and functionalized PIB, in the presence of titanium tetrabutoxide as catalyst. a,o -Dianhydride [58] and dihydroxyl-terminated PIB of molecular weights 1000, 2200, 4800, and 10000 g/mole were used (Schemes 17 and 18). A multiblock copolymer with PBT and... 

The exo-olefin is a precursor to a variety of chain-end-functionalized polymers via postpolymerization reaaions as shown in Scheme 37. Hydroxy-functionalized PIB has been utilized as a precursor for the preparation of RAFT macromo-lecular CTAs and carboxylic acid end-fimctionalized polymers. Telechelic PIB diols have been prepared using p-dicumyl chloride/BCU initiator system followed by dehydro-chlorination, hydroboration, and alkaline peroxide oxidation. Aldehyde end-fiinctionalized PIBs have been used to prepare carboxyl- and hydroxyl-terminated poly-mers. Carboxylic acid-functionalized PIBs have also been prepared from the oxidation of the methyl ketone-functionalized PIBs." The hydroxyl-functionalized PIBs have also been used to prepare methacrylate macromonomers by their reaction with methacryloyl chloride in the presence of triethylamine. The homopolymerization and copolymerization of these maaomonomers with methyl methacrylate were also reported. Cyanoacrylate-funaionalized PIBs prepared via the hydroxyl-functionalized PIB were also reported by Kennedy et al. ... 

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